Upgrade to draft version 07 (#9)

README.md

@@ -36,7 +36,7 @@
 
 # SD-JWT Reference implementation
 
-Rust implementation of the [Selective Disclosure for JWTs (SD-JWT) **version 06**](https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-06.html)
+Rust implementation of the [Selective Disclosure for JWTs (SD-JWT) **version 07**](https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html)
 
 ## Overview
 

src/decoder.rs

@@ -84,6 +84,12 @@ impl SdObjectDecoder {
     // Decode the object recursively.
     let mut decoded = self.decode_object(object, &disclosures_map, &mut processed_digests)?;
 
+    if processed_digests.len() != disclosures.len() {
+      return Err(crate::Error::UnusedDisclosures(
+        disclosures.len().saturating_sub(processed_digests.len()),
+      ));
+    }
+
     // Remove `_sd_alg` in case it exists.
     decoded.remove(SD_ALG);
     Ok(decoded)
@@ -139,6 +145,7 @@ impl SdObjectDecoder {
             if output.contains_key(&claim_name) {
               return Err(Error::ClaimCollisionError(claim_name));
             }
+            processed_digests.push(digest_str.clone());
 
             let recursively_decoded = match disclosure.claim_value {
               Value::Array(ref sub_arr) => Value::Array(self.decode_array(sub_arr, disclosures, processed_digests)?),
@@ -199,11 +206,11 @@ impl SdObjectDecoder {
             if processed_digests.contains(&digest_in_array) {
               return Err(Error::DuplicateDigestError(digest_in_array));
             }
-
             if let Some(disclosure) = disclosures.get(&digest_in_array) {
               if disclosure.claim_name.is_some() {
                 return Err(Error::InvalidDisclosure("array length must be 2".to_string()));
               }
+              processed_digests.push(digest_in_array.clone());
               // Recursively decoded the disclosed values.
               let recursively_decoded = match disclosure.claim_value {
                 Value::Array(ref sub_arr) => {
@@ -245,6 +252,7 @@ impl Default for SdObjectDecoder {
 
 #[cfg(test)]
 mod test {
+  use crate::Disclosure;
   use crate::Error;
   use crate::SdObjectDecoder;
   use crate::SdObjectEncoder;
@@ -281,4 +289,48 @@ mod test {
     let decoded = decoder.decode(encoder.object(), &vec![]).unwrap();
     assert!(decoded.get("_sd_alg").is_none());
   }
+
+  #[test]
+  fn duplicate_digest() {
+    let object = json!({
+      "id": "did:value",
+    });
+    let mut encoder = SdObjectEncoder::try_from(object).unwrap();
+    let dislosure: Disclosure = encoder.conceal(&["id"], Some("test".to_string())).unwrap();
+    // 'obj' contains digest of `id` twice.
+    let obj = json!({
+      "_sd":[
+        "mcKLMnXQdCM0gJ5l4Hb6ignpVgCw4SfienkI8vFgpjE",
+        "mcKLMnXQdCM0gJ5l4Hb6ignpVgCw4SfienkI8vFgpjE"
+      ]
+      }
+    );
+    let decoder = SdObjectDecoder::new_with_sha256();
+    let result = decoder.decode(obj.as_object().unwrap(), &vec![dislosure.to_string()]);
+    assert!(matches!(result.err().unwrap(), crate::Error::DuplicateDigestError(_)));
+  }
+
+  #[test]
+  fn unused_disclosure() {
+    let object = json!({
+      "id": "did:value",
+      "tst": "tst-value"
+    });
+    let mut encoder = SdObjectEncoder::try_from(object).unwrap();
+    let disclosure_1: Disclosure = encoder.conceal(&["id"], Some("test".to_string())).unwrap();
+    let disclosure_2: Disclosure = encoder.conceal(&["tst"], Some("test".to_string())).unwrap();
+    // 'obj' contains only the digest of `id`.
+    let obj = json!({
+      "_sd":[
+        "mcKLMnXQdCM0gJ5l4Hb6ignpVgCw4SfienkI8vFgpjE",
+      ]
+      }
+    );
+    let decoder = SdObjectDecoder::new_with_sha256();
+    let result = decoder.decode(
+      obj.as_object().unwrap(),
+      &vec![disclosure_1.to_string(), disclosure_2.to_string()],
+    );
+    assert!(matches!(result.err().unwrap(), crate::Error::UnusedDisclosures(1)));
+  }
 }

src/disclosure.rs

@@ -10,7 +10,7 @@ use std::fmt::Display;
 /// Represents an elements constructing a disclosure.
 /// Object properties and array elements disclosures are supported.
 ///
-/// See: https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-06.html#name-disclosures
+/// See: https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html#name-disclosures
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct Disclosure {
   /// The salt value.
@@ -69,7 +69,7 @@ impl Disclosure {
     if decoded.len() == 2 {
       Ok(Self {
         salt: decoded
-          .get(0)
+          .first()
           .ok_or(Error::InvalidDisclosure("invalid salt".to_string()))?
           .as_str()
           .ok_or(Error::InvalidDisclosure(
@@ -87,7 +87,7 @@ impl Disclosure {
     } else if decoded.len() == 3 {
       Ok(Self {
         salt: decoded
-          .get(0)
+          .first()
           .ok_or(Error::InvalidDisclosure("invalid salt".to_string()))?
           .as_str()
           .ok_or(Error::InvalidDisclosure(
@@ -140,7 +140,7 @@ mod test {
   use super::Disclosure;
 
   // Test values from:
-  // https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-05.html#appendix-A.2-7
+  // https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html#appendix-A.2-7
   #[test]
   fn test_parsing() {
     let disclosure = Disclosure::new(

src/error.rs

@@ -39,4 +39,7 @@ pub enum Error {
 
   #[error("salt size must be greater than or equal to 16")]
   InvalidSaltSize,
+
+  #[error("the validation ended with {0} unused disclosure(s)")]
+  UnusedDisclosures(usize),
 }

src/hasher.rs

@@ -15,7 +15,7 @@ pub const SHA_ALG_NAME: &str = "sha-256";
 ///
 /// Implementations of this trait are expected only for algorithms listed in
 /// the IANA "Named Information Hash Algorithm" registry.
-/// See [Hash Function Claim](https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-06.html#name-hash-function-claim)
+/// See [Hash Function Claim](https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html#name-hash-function-claim)
 pub trait Hasher: Sync + Send {
   /// Digests input to produce unique fixed-size hash value in bytes.
   fn digest(&self, input: &[u8]) -> Vec<u8>;
@@ -60,7 +60,7 @@ impl Hasher for Sha256Hasher {
   }
 }
 
-// Some test values taken from https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-05.html#name-hashing-disclosures
+// Some test values taken from https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html#name-disclosures
 #[cfg(test)]
 mod test {
   use crate::Hasher;

src/key_binding_jwt_claims.rs

@@ -11,13 +11,12 @@ use crate::Hasher;
 use serde::Deserialize;
 use serde::Serialize;
 
-///
+/// Claims set for key binding JWT.
 #[derive(Clone, Debug, Default, PartialEq, Eq, Deserialize, Serialize)]
 pub struct KeyBindingJwtClaims {
   pub iat: i64,
   pub aud: String,
   pub nonce: String,
-  #[serde(rename = "_sd_hash")]
   pub sd_hash: String,
   #[serde(flatten)]
   pub properties: BTreeMap<String, Value>,
@@ -27,7 +26,7 @@ impl KeyBindingJwtClaims {
   pub const KB_JWT_HEADER_TYP: &'static str = " kb+jwt";
 
   /// Creates a new [`KeyBindingJwtClaims`].
-  /// When `issued_at` is left as None, it will automatically default to the current time
+  /// When `issued_at` is left as None, it will automatically default to the current time.
   ///
   /// # Panic
   /// When `issued_at` is set to `None` and the system returns time earlier than `SystemTime::UNIX_EPOCH`.

tests/api_test.rs

@@ -18,7 +18,7 @@ use sd_jwt_payload::SdObjectEncoder;
 
 #[test]
 fn test_complex_structure() {
-  // Values taken from https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-06.html#appendix-A.2
+  // Values taken from https://www.ietf.org/archive/id/draft-ietf-oauth-selective-disclosure-jwt-07.html#appendix-A.2
   let object = json!({
     "verified_claims": {
       "verification": {